CN117099493A

CN117099493A - Centrifugal pump with cooling of electronics within electronics housing

Info

Publication number: CN117099493A
Application number: CN202280024904.0A
Authority: CN
Inventors: F·迪桑托; D·克里尔; M·利博尼; C·普雷罗; M·施韦特
Original assignee: KSB SE and Co KGaA
Current assignee: KSB SE and Co KGaA
Priority date: 2021-04-01
Filing date: 2022-03-30
Publication date: 2023-11-21
Also published as: EP4316223A1; DE102021001714A1; WO2022207725A1

Abstract

The invention relates to a centrifugal pump having a two-part electronics housing, wherein a first housing part is a cooling body and a circuit board having electronic components is supported in the electronics housing, characterized in that at least one IC module is mounted on the circuit board in a vertical embodiment, which IC module is oriented in the direction of the first housing part in the inserted position, and the first housing part has at least one slot-shaped recess in its housing wall facing the IC module for receiving the IC module.

Description

Centrifugal pump with cooling of electronics within electronics housing

Technical Field

The invention relates to a centrifugal pump with a two-part electronics housing, wherein a first housing part is a cooling body and at least one circuit board with electronic components is mounted in the electronics housing.

Background

As the energy efficiency requirements of pumps become higher, the electronics of centrifugal pumps become more complex. In particular in the field of heating circulation pumps, energy-efficient pump operation requires rotational speed regulation in order to be able to adapt the current pump rotational speed dynamically to the current plant conditions and environmental conditions. In order to adapt the rotational speed accordingly, a frequency converter is necessary, the power module of which in particular requires semiconductor switches.

The semiconductor switches can be operated at high switching frequencies, which leads to increased switching losses and, consequently, increased heat loss. The heat losses that are generated must be removed from the electronics housing to the surrounding environment by appropriate measures, otherwise there is a threat of serious thermal damage to the components. In this context, the electronics housing is formed at least in part by a first housing part which at the same time assumes the function of a cooling body for the outward heat dissipation. For optimum heat removal, the component with the highest thermal expansion is ideally directly thermally conductively coupled to the coolant.

However, depending on design considerations, direct thermal coupling is not always possible, for example, due to the different component heights. It is therefore necessary in part to equip individual components, in particular modules with integrated circuits (IC modules), with special additional cooling bodies within the electronics housing. One example for such an IC module is a set of structures for implementing a power correction filter. A separate cooling body adapted to the module package is fastened directly at the module housing. It is important here that the heat sink is pressed onto the surface of the IC module with the required contact pressure, which makes the assembly, which is often achieved by a threaded connection, more complex and costly. In addition to the assembly effort thus increased, the cost of the individual parts in mass production naturally increases due to the additional components.

Disclosure of Invention

The object of the present invention is therefore to create a cost-effective electronic device for a centrifugal pump, which can be implemented in particular in a small and space-saving manner and which reduces the number of components required.

This object is achieved by a centrifugal pump having the features of claim 1. Advantageous embodiments of the centrifugal pump are the subject matter of the dependent claims.

According to the invention, at least one module with an integrated circuit (IC module) is mounted on a circuit board in a vertical embodiment. Such an IC module has a chip with an integrated circuit arranged, which is encapsulated in a module housing for protection and easier contact. The IC module may be an electronic component with increased cooling requirements, which in conventional embodiments requires a dedicated cooling body. When the IC module is oriented vertically on the circuit board, its large-area side faces preferably protrude perpendicularly from the circuit board, while the laterally or longitudinally extending end faces of the module housing are oriented parallel to the circuit board, either against the circuit board or at a small distance.

By the vertical implementation of the IC module and its vertical assembly or laying on the circuit board, the space requirements required on the circuit board are reduced. Furthermore, the following possibilities are obtained: the IC module is inserted into the slot of the opposing housing wall, i.e. the component can be inserted into the slot of the first housing part and thus be directly thermally coupled to the heat sink. The removal of the generated heat loss can thus be better achieved by the housing part being embodied as a heat sink and a separate, dedicated heat sink for the IC module can be dispensed with. This reduces the time required for assembly of the pump, and reduces the individual costs by eliminating additional components.

The dimensions of the slot are ideally adapted to the strength or thickness of the IC module (i.e., the package size of the module housing). The minimized gap size between the slot walls and the member ensures improved thermal bonding while the member can be additionally stabilized and secured by the cooling body.

It is particularly advantageous if opposing large-area side walls of the module housing of the IC module bear against the slot walls. Thereby achieving cooling of both sides of the IC module. It can furthermore be provided that at least one longitudinally or transversely extending end face of the module housing bears against the slot bottom. Alternatively, the longitudinally extending or transversely extending end sides may also be spaced apart from the slot bottom. The end side protruding perpendicularly from the circuit board may be exposed to the outside.

It may be provided that the slot is formed directly by a recess introduced into the housing wall. However, this requires a certain minimum strength of the housing wall. It is therefore preferable to form one or more projections on the inner housing wall of the first housing part, which projections project in the direction of the circuit board. A single projection with a slot-like depression is conceivable. It is also conceivable to form at least two individual projections whose spatial distance relative to one another defines the slot.

The shape of the one or more protrusions is essentially arbitrary. If two projections are provided, these projections should each be embodied with at least one surface projecting perpendicularly from the housing wall. The vertically projecting faces of the at least two projections are opposed and thus form a slot wall. At least one, preferably both, of the projections may be shaped in a ramp-like manner.

It can also be provided that the slot or slot opening is formed with one or more insertion aids in order to be able to more easily insert the IC module into the corresponding slot opening when the pump electronics are assembled. It has proven to be advantageous if such an insertion aid is embodied in the form of an insertion bevel in the region of the slot opening. If the slot is formed by a vertically projecting face, the vertically projecting face has an outwardly extending inclined portion at its outer end.

It is expedient if the electronic circuit board is supported by the first housing part (i.e. the heat sink) so that the IC module is introduced into the slot of the heat sink provided for this purpose in conjunction with the assembly of the circuit board.

Since the cooling body is usually composed of a metal or an electrically conductive material, the cooling body is often grounded. The electrically conductive nature of the heat sink necessitates electrical insulation between the IC module and the heat sink. It is also desirable to optimize the thermal coupling between the components. This can be achieved by introducing additional thermal pads between the IC module and the cooling body, i.e. the slot wall.

The above-mentioned thermal pad is placed onto the IC module before the circuit board is assembled in the cooling body, and it is desirable to cover at least the side of the IC module housing that contacts the cooling body, at least the two large-area side walls of the IC module housing and the longitudinally-extending or laterally-extending end sides with the thermal pad. The thermal pad may be bonded to a side of the IC module. According to a preferred embodiment, the thermal pad used can be composed of a tear-resistant material, so that no undesired material wear occurs due to shear or friction forces occurring when the bonded IC module is introduced into the recess of the cooling body. For example, the thermal pad may be made of a reinforced material, including in particular a woven mesh.

The mentioned IC module is preferably a module of a power electronics, which is characterized by a relatively large cooling requirement. For example, it is conceivable that the IC module is a power factor correction filter (PFC) module of the pump electronics. The IC module may have a DIP housing that enables a vertical mounting on a circuit board. The circuit board may be equipped on a single side or on both sides. In the case of single-sided installations, the available circuit board space can be optimally utilized by vertical installation.

The slot in the wall of the first housing part may be opened already at the time of manufacturing the housing blank, which is preferably shaped by a casting method. Alternatively, the slot can be produced afterwards by a cutting method, in particular by milling. However, the latter implies an additional production step.

The centrifugal pump may preferably be an in-line pump, and particularly preferably a heating circulation pump.

Drawings

Further advantages and features of the invention are explained in more detail below on the basis of the embodiments shown in the drawings. Wherein:

fig. 1 shows a top view of a main circuit board of pump electronics for a heating circulation pump, and

fig. 2 shows a detailed illustration of an IC module being introduced into a slot.

Detailed Description

The embodiments described below show a centrifugal pump according to the invention, which is here embodied by way of example as a heating circulation pump. Fig. 1 shows a main circuit board 1 for a pump electronics, which circuit board has a large number of electronic components for implementing a frequency converter.

In addition to the components of the input and intermediate circuits and the power electronics of the frequency converter, a power correction filter 10 is likewise installed, which should reduce the grid load by suppressing unwanted harmonics. In addition to the diode, such PFCs also comprise at least one semiconductor switching element, the switching process of which causes increased heat loss. In the illustrated embodiment, the invention is illustratively explained in terms of a power correction filter in the form of a PFC module. Of course, other IC modules are within the scope of the invention.

In the exemplary embodiment shown in fig. 1, the circuit board 1 is equipped on only one side, wherein the equipped circuit board side 1a faces the cooling body 20 in the installed position (see fig. 2). For cost and space reasons, the circuitry of the power correction filter 10 is not formed by a separate component, but instead the integrated circuit (IC module), i.e. the PFC module 10, is soldered to the circuit board 1, for example using the DIP housing (dual in-line package) shown. However, the PFC module 10 is not soldered to the circuit board surface 1a in a horizontal configuration, but instead is soldered vertically, so that the largest sides 10a, 10b of the PFC module protrude perpendicularly from the circuit board side 1 a. By utilizing the DIP housing embodiment, the metal legs of the module 10 are guided through the drilled holes onto the unassembled circuit board side and soldered there.

The electronics housing of the centrifugal pump is furthermore embodied in two parts, wherein the first housing part is formed from a metallic cooling body 20, in particular formed from aluminum. The electronics board 1 is supported on the inside of the cooling body 20 and is additionally fastened, in particular screwed, thereto. In the inserted position, the equipped circuit board side 1a therefore faces the inner wall of the cooling body 20. On the inner housing wall of the cooling body 20, at the level of the PFC module 10, two projections 21a, 21b of ramp-like design of the cooling body 20 are present, which are spatially separated from one another. The walls 22a, 22b of the projections 21a, 21b projecting perpendicularly to the inner wall of the housing are opposite and form a slot 23 according to the invention for receiving the PFC module 10. The spacing of the walls 22a, 22b relative to each other and their dimensions are coordinated with the thickness and height of the PFC housing so that the module 10 fits into the slot with as small a gap size as possible.

When the electronic circuit board 1 is mounted on the structure of the cooling body 20, the PFC module 10 is simultaneously pushed into the slot 23, wherein the large-area sides 10a and 10b of the PFC module 10 are in contact with the vertically projecting slot walls 22a, 22b, so that a desired thermal coupling between the PFC module 10 and the cooling body 20 takes place and cooling of both sides of the module 10 is achieved.

In the region of the upper ends of the vertical slot walls 22a, 22b, outwardly directed inclined portions 24a, 24b are provided, which serve as insertion aids when the PFC module 10 is mounted and inserted on a circuit board. For optimal thermal coupling and simultaneous electrical insulation of the PFC module 10 to the metallic heat sink 20, the thermal pad 11 is applied to the PFC module 10 before the circuit board assembly, so that the large-area side walls 10a, 10b of the PFC module 10 are covered and the upper longitudinal end face is covered. The thermal pad 11 is composed of a flat and flexible material that adheres at least to the side walls 10a, 10b of the PFC module. The material of the thermal pad is reinforced by the woven mesh in order to prevent or minimize damage to the pad surface caused by friction when the module 10 is introduced into the slot 23.

It can also be seen that the heat conducting pad 11 does not end with the side faces 10a, 10b in the region of the printed circuit board 1, but rather protrudes from said side faces and is bent or rolled outwards. The pad 11, which is not shown in fig. 2 for the sake of clarity, is thus also between the projections 21a, 21b in the region of the projection lead-in inclinations 24a, 24b and the circuit board 1, so that here too an electrical insulation of the metallic projections 21a, 21b with respect to the circuit board 1 is ensured.

Claims

1. A centrifugal pump with a two-part electronics housing, wherein a first housing part (20) is a cooling body and at least one circuit board (1) with electronic components (10) is mounted in the electronics housing (20),

it is characterized in that the method comprises the steps of,

at least one IC module (10) is mounted on the circuit board (1) in a vertical embodiment, the IC module being oriented in the direction of the first housing part (20) in the installed position, and the first housing part (20) having at least one slot-shaped recess (23) in its housing wall facing the IC module (10) for receiving the IC module (10).

2. Centrifugal pump according to claim 1, characterized in that opposing large-area side walls (10 a, 10 b) of a module housing of the IC module (10) bear against slot walls (22 a, 22 b).

3. Centrifugal pump according to one of the preceding claims, characterized in that the longitudinally or transversely extending end sides of the IC module housing (10) are introduced into the slot-shaped recess (23) against the slot bottom of the slot-shaped recess (23) or at a distance from the slot bottom.

4. Centrifugal pump according to any one of the preceding claims, wherein the slot (23) of the housing part (20) is formed by one or more protrusions (21 a, 21 b) of the housing wall protruding in the direction of the circuit board (1).

5. Centrifugal pump according to claim 4, wherein the slot (23) is formed by two ramp-like projections (21 a, 21 b), the vertically projecting faces (22 a, 22 b) of which are opposite and form the slot (23).

6. Centrifugal pump according to one of claims 4 or 5, characterized in that one or more introduction aids (24 a, 24 b) are provided in the region of the slot opening, in particular in that the vertically projecting faces (22 a, 22 b) have an outwardly extending introduction slope (24 a, 24 b) at the outer end.

7. Centrifugal pump according to any one of the preceding claims, wherein the circuit board (1) is received and supported, in particular fastened, by the first housing part (20).

8. Centrifugal pump according to any one of the preceding claims, wherein at least one thermal pad (11) is introduced between the IC module (10) and the slot walls (22 a, 22 b) for thermal bonding and/or electrical insulation.

9. Centrifugal pump according to claim 8, wherein the thermal pad (11) is bonded to an IC module housing wall, in particular to two large-area side walls (10 a, 10 b) and/or to a longitudinally or transversely extending end side of the IC module housing.

10. Centrifugal pump according to any one of claims 8 or 9, wherein the heat conducting pad (11) comprises a material reinforcement, in particular in the form of a woven mesh, and/or extends onto the contact site between the IC module (10) and the circuit board (1) and is rolled out in order to prevent the protrusions (21 a, 21 b) from being in direct contact with the circuit board (1).

11. Centrifugal pump according to any one of the preceding claims, wherein the IC module (10) has a DIP housing and/or a power module, in particular a power correction filter module.

12. Centrifugal pump according to any one of the preceding claims, wherein the slot (23) is manufactured by milling or is an integral part of a cast housing blank.

13. Centrifugal pump according to any one of the preceding claims, wherein the centrifugal pump is an in-line pump, in particular a heating circulation pump.